3-secondary aminomethylene-4-lower-alkyl-5-azo-6-hydroxypyrid-2-one dyestuffs

ABSTRACT

A water-soluble salt of a 3-tertiary amino-5-azo-6-hydroxypyrid2-one of the formula   WHEREIN A is phenyl, napthyl or phenyl substituted with one or two substituents selected from nitro, methyl, methoxy, halogen, acetamido, sulphonamido, phenylazo and tolyazo, T is methyl, ethyl, propyl, phenyl or tolyl, Y is hydrogen, methyl, ethyl, propyl, hydroxyethyl, methoxypropyl, napthyl, phenyl, or phenyl substituted with nitro, chloro, methyl, or methoxy and X is amino of the formula -NR1R2 wherein R1 and R2 are methyl, ethyl, propyl, hydroxyethyl or cyanoethyl or together with the nitrogen to which they are attached form a piperidino, morpholino, thiomorpholino, hexahydroazepino or 2-methylpyrrolidino ring. The dyestuff is prepared by reacting the 3-halogen derivative or said dyestuff with a secondary amine of the formula NHR1R2 wherein R1 and R2 are defined above and forming the salt of the resulting product with an inorganic or organic acid. The dyestuff is used to dye polymeric materials, particularly polyacrylonitrile distinguished by good wet and light fastness and build up properties.

ite tates atnt [191 Hughes [451 Mar. 4, 1975 [75] Inventor: NigelHughes, Manchester, England [73] Assignee: Imperial Chemical IndustriesLimited, London, England [22] Filed: Dec. 27, 1971 [21] App], No.:212,634

[30] Foreign Application Priority Data Jan. 4, 1971 Great Britain 292/71[52] US. Cl 260/156, 8/41 R, 8/41 A, 8/41 B, 8/50, 8/92, 260/154 [51]Int. Cl. C091) 29/36, D06p 3/70 [58] Field of Search 260/156, 296 R [56]References Cited UNITED STATES PATENTS 1,887,772 11/1932 Martin et a].260/5709 2,263,387 11/1941 Houk et al. 260/570.9 X 2,431,190 11/1947Morgan 260/156 X 2,505,133 4/1950 Miescher et al. 260/570.9 X 2,512,7326/1950 Aeschlimann et al. 260/296 R 2,573,606 10/1951 Rieveschl et a1260/570.9 2,608,584 8/1952 Spruzes et a1 260/570.9 2,860,141 ll/l958Larrabee 260/156 X 2,951,078 8/1960 Biel 260/296 R X 3,487,066 12/1969Ritter et a1 260/156 3,640,674 2/1972 Bertie et a1. 260/156 X 3,657,2144/1972 Bertie et a1. 260/156 3,664,996 5/1972 Berrie et a1. 260/156OTHER PUBLICATIONS Ettel et al., Chemical Abstracts, Vol. 45, 3847,(1951). Wagner et al., "Synthetic Organic Chemistry, pages 666 to 670,(1953).

Kuhn et al., Ber. Deut. Chem. GeselL, Vol. 70, pages 567 to 569, (1937).

Smirnov et al., Chemical Abstracts, Vol. 62, 11,774, (1965).

Primary ExaminerFloyd D. Higel Attorney, Agent, or Firm-Cushman, Darby &Cushman [5 7] ABSTRACT A water-soluble salt of a 3-tertiaryamino-5-azo-6- hydroxypyrid-2-one of the formula wherein A is phenyl,napthyl or phenyl substituted with one or two substituents selected fromnitro, methyl, methoxy, halogen, acetamido, sulphonamido, phenylazo andtolyazo, T is methyl, ethyl, propyl, phenyl or tolyl, Y is hydrogen,methyl, ethyl, propyl, hydroxyethyl, methoxypropyl, napthyl, phenyl, orphenyl substituted with nitro, chloro, methyl, or methoxy and X is aminoof the formula -NR R wherein R and R are methyl, ethyl, propyl,hydroxyethyl or cyanoethyl or together with the nitrogen to which theyare attached form a piperidino, morpholino, thiomorpholino,hexahydroazepino or Z-methylpyrrolidino.

ring. The dyestuff is prepared by reacting the 3- halogen derivative orsaid dyestuff with a secondary amine of the formula Nl-IRR wherein R andR are defined above and forming the salt of the resulting product withan inorganic or organic acid. The dyestuff is used to dye polymericmaterials, particularly polyacrylonitrile distinguished by good wet andlight fastness and build up properties. i

' 3 Claims, No Drawings S-SECONDARYAM1NOMETHYLENE-4-LOWER-ALKYL-5-AZO-6- HYDROXYPYRID-Z-ONE DYESTUFFS Thisinvention relates to new azo dyestuffs which are valuable for thecoloration of polymeric materials in the form of fibres, film, threadsor tapes and particularly of polymeric materials consisting ofpolyesters, polyamides, cellulose esters or polymers or copolymers ofacrylonitrile or dicyanoethylene.

According to the invention there are provided new azo dyestuffs freefrom sulphonic or carboxylic acid groups of the formula:

l A '"f a (I) L The aromatic radical which is represented by A may beany aromatic carbocyclic or heterocyclic radical which may carrysubstituents such as alkyl, cycloalkyl or aralkyl, alkoxy, aralkoxy,aryl, carbalkoxy, acyloxy, aryloxy, naphthylazo, acylamino, aryloxy,arylamino. carbamoyl, sulphamyl, alkylsulphonyl, alkylmercapto,aralkylmercapto, dialkylamino and substituted derivatives of theforegoing, nitro, cyano, trifiuoromethyl and halogeno groups,

A is preferably a radical of the benzene, naphthalene, or hetercyclicclass, especially suitable substituents being Cl, Br, CF CN, N NH- COCHOH,

Especially valuable dyestuffs are obtained whenA is an optionallysubstituted o-nitroaryl radical, particularly o-nitrophenyl, whichafford colorations of superior light fasteness.

The tertiary amino group represented by X will be of the formula -NRRwherein R is an alkyl, alkenyl, aralkyl, or cycloalkyl group orsubstituted derivative thereof and R is a group of the type representedby R. or an aryl substituted aryl group or, alternatively the groups Rand R together with the nitrogen atom form a heterocyclic ring.

As groups which may be represented by R or R there are mentioned alkylgroups, for example methyl, ethyl, isopropyl and tert.-butyl,substituted alkyl groups, for example a-hydroxyetlhyl, ,B-cyanoethyl andy-methoxy propyl, alkenyl groups for example allyl, cycloalkyl groupsfor example cyclopentyl and cyclohexyl, substituted cycloalkyl groupsfor example chlorocyclohexyl and methoxycyclohexyl, aralkyl groups forexample benzyl and B-phenylethyl, and substituted aralkyl groups forexample p-nitrobenzyl, pmethoxybenzyl and B-(4-chlorophenyl)ethyl.

As optionally substituted aryl groups which may be represented by Rthere are mentioned phenyl, o-, mand p-tolyl, o-, mand p-chlorphenyl andpmethoxyphenyl.

As heterocyclic groups which may be formed by R, R and the nitrogen atomthere are mentioned for example especially piperidino but alsomorpholino, pyrrolidino, thiamorpholino, piperazino andhexahydroazepino.

The optionally substituted alkyl radicals represented by Y arepreferably optionally substituted lower alkyl radicals, by which ismeant alkyl radicals containing not more than 4 carbon atoms and theirsubstituted derivatives, and as specific examples of such radicals theremay be mentioned particularly ethyl but also methyl, n-propyl, andn-butyl, hydlroxy lower alkyl such as B-hydroxyethyl, lower alkoxy loweralkyl such as ,B-(methoxy or ethoxy) ethyl, cyanomethyl, carbamoyLmethyl, carbethoxymethyl and acetylmethyl.

As examples of optionally substituted alkenyl, aralkyl, and cycloalkylradicals which may be represented by Y, there are mentioned the groupsofthis type which may be represented by R and R. As examples ofoptionally substituted aryl groups which may be represented by Y thereare mentioncd phenyl, o-, mand ptolyl, o-, mand p-chlorophenyl,p-methoxyphenyl, lnaphthyl, p-sulphondimethylamidlophenyl, 0-, in andp-nitrophenyl, p-acetamidophenyl, p-acetylphenyl and m-alkyl (or aryl)sulphonylphenyl.

As lower alkyl groups which are represented by T there are mentionedalkyl groups containing not more than 4 carbon atoms, especially themethyl group.

As aryl groups which may be represented by T there are mentioned forexample phenyl and 0-, mand ptolyl groups,

n is preferably 1.

As salts of the azo dyestuffs there are mentioned for example salts withinorganic acids, such as hydrochloric acid, sulphuric acid, phosphoricsulphamic and boric acid, and with organic acids such as formic acid,acetic acid, propionic acid, citric acid, oxalic acid, and mono, di andtrichloracetic acids.

These salts may be obtained in aqueous solution by dissolution of theamine in water and an equivalent quantity of the acid and may beisolated by evaporation of the aqueous solution, or by salting out thedye from the aqueous solution. In some cases the dyes is isolated as itstetrachlorozincate by addition of salt and zinc chloride to its aqueoussolution.

Alternatively, the dye free base may be ground with a solidwater-soluble acid such as sulphamic or citric acid and then pasted witha little aqueous acetic or propionic acid to give a water-solubledyestuft'.

According to the invention there is also provided a process for thepreparation of dye-stuffs of the formula I which comprises reacting ahalogenomethyl compound of the formula CH HMl wherein A, T, Y and n havethe meanings given hereinbefore and Hal is a chlorine or bromine atomwith a secondary amine of the formula Nl-lRR wherein R and R have themeanings given hereinbefore.

The process of the invention may be carried out by heating togetherequivalent quantities of the halogenomethyl compound and the secondaryamine in a suitable inert solvent or in an excess of the secondary amineas solvent followed by isolation of the tertiary amine by conventionalmethods.

As examples of secondary amines there are mentioned alkylamines such asdimethylamine, diethylamine, di isopropylamine, substituted alkylaminessuch as diethanolamine, di-(a-methoxypropyl) amine and N- methylbenzylamine, aromatic amines such as N- methyl aniline and N-phenylbenzylamine and heterocyclic amines such as pyrrolidine, piperidine,morpholine, thiamorpholine, hexamethyleneimine, and piperazine.

The compounds of the Formula ll used in the process of the invention arethemselves novel and may be prepared by halogenomethylation of anazohydroxypyridone of the formula A N w m (111) .mo 3 o wherein A, T, Yand n have the meanings given hereinbefore.

The halogenomethylation may be carried out by any conventional procedurefor this type of reaction, for example the azohydroxypyridone may beheated in a suitable solvent such asdioxane, chlorobenzene or analcohol, with formaldehyde and hydrochloric acid.

Alternatively the azo pyridone compound may be treated withparaformaldehyde in a mixture of sulphuric and chlorosulphuric acids orwith paraformaldehyde and sodium chloride in concentrated sulphuric acidor with sym.-dichlorodimethyl-etherin concentrated sulphuric acid. Thesereactions are preferably carried out at a temperature of between and100C.

There is also provided an alternative process for the preparation ofdyestuffs of the formula I which comprises reacting a compound of theformula III with formaldehyde or a formaldehyde generator and asecondary amine of the formula NHR, R wherein A, T, Y, n, R and R havethe meanings given hereinbefore.

The alternative process may be carried out under conventional conditionsfor this type of reaction (the line-2-,

Mannich reaction), for example the compound of formula lIl may be heatedwith a secondary amine of the formula NHRR and with paraformaldehyde inan inert solvent such as dioxane, methanol, ethanol, isopropanol,toluene, ethylene glycol, acetic acid, and es pecially halogenatedaromatic hydrocarbon such as chlorobenzene, o-dichlorobenzene, andbromobenzene and halogenated aliphatic compounds such as ethylenedichloride and propylene dichloride. The dyestuff so produced may thenbe isolated by precipitation with water followed by filtration or otherconventional methods.

The azohydroxypyridones are obtained by diazotizing an amine of theformula A(NH and coupling the diazonium compound with the correspondinghydroxypyridone. Examples of suitable amines include aniline, o-, morp-toluidine, 0-, mor p-anisidine, o-, m-, or pchloroaniline, o-, morp-bromoaniline, o-, mor pnitroaniline, 2,5-dichloroaniline,2,4-dinitroaniline, 2,4-dinitro-6-(chloro or bromo)aniline, 4-methanesulphonylaniline, 4-aminobenzotrifluoride, 4- or5-nitro-2-toluidine, 4- or 5-nitro-2-anisidine, 4- or5-bromo-2-anisidine, 2,6-di(chloroor bromo-)-4- nitroaniline,2,4,6-trinitroaniline, 2,4-dinitro-6-carbomethoxyaniline,2-amino-S-nitrobenzotrifluoride, 2,4-bis(methane-sulphonyl) aniline,2-(chloroor bromo-)-4-nitroaniline, methylanthranilate, 4- or 5-nitromethylanthranilate, 4-amino-benzamide, 2,6- di(chloroorbromo-)aniline-4-sulphonamide, 2,6- di(ch1oroorbromo-)-4-methylsulphonylaniline, 2,5- di-(chloroor bromo-)-4,6-dinitroaniline, 2-amino- 3,5-dinitrobenzotrifluoride,3-amino-2-(chloroor bromo-)-4,6-dinitro-(toluene or anisole), 3-amino-4-(chloroor bromo-)-2,6-dinitro-(toluene or anisole), 2- or4-cyanoaniline, 4-nitro-2-cyanoaniline, 2,4-dinitro- 6-cyanoaniline,2-nitro-4-cyano aniline, 2-chlor0-4- cyanoaniline,3-amino-2,4,6-trinitrotoluene, Z-(chloroorbromo-)-4-methylsulphonylaniline, 3-(chloroor bromo-)-4-thiocyanatoaniline, 2-(chloroor bromo-)- 4-sulphamylaniline,2-amino-5-nitrophenylmethanesulphone,2-amino-3,5-dinitrophenylmethylsulphone, 2-amino-3-(chloroorbromo-)-5-nitrophenylmethylsulphone, 2-sulphamyl-4-nitroaniline,Z-methylsulphamyl-4-nitroaniline, 2-ethylsulphamyl-4-nitroaniline, 2-butylsulphamyl-4-nitroaniline, 2-dimethylsulphamyl-4- nitroaniline,2-methylsulphamyl-4,o-dinitroaniline, 2-methylsulphamyl-4-nitro6-(chloroor bromo-) aniline,2-phenylsulphamyl-4-nitroaniline, methyl 2- amino-3-(chloroorbromo-)-5-nitrobenzoate, dimethyl Z-aminoterephthalate, dimethyl2-amino-5- nitroterephthalate, aniline -2-, 3- or 4- sulphamate, ani- 3-or 4-N,N-dimethylsulphamate, 4- aminobenzenesulphonamide,2-nitro-4-methylaniline, 2-cyano-4-methylaniline,4-chloro-2-methylaniline, 2- aminothiazole,2-amino-6-methoxybenzthiazole, 2-amino-6-methylsulphonyl benzthiazole,2-amino-6- nitrobenzthiazole, Z-aminobenzthiazole, 2,5-dimethoxyaniline, 2-amino-5-nitrothiazole, 2-amino-4-methyl-S-nitrothiazole, 2-amino-4m-nitrophenyl-5- nitrothiazole,3-methyl-5-amino-l,2,4-thiadiazole, 3- methylsulphonyl-S-amino-l,2,4-thiadiazole, 3- methylmercapto-S-amino-l,2,4-thiadiazole, 3-phenyl-5-amino-1,2,4-thiadiazole, 2-aminol ,3,4-thiadiazole,2-amino-5-nitro-l,3,4-thiadiazole, 4-aminobenzene- (2,5- or3,5-dichloro)benzenesulphon-, N- dimethylamide,4-amino-3-chlorobenzenesulphon- N,N-dimethylamide,5-chloro-2,4-bis-(N,N-dimethylaminosulphonyl)aniline,2-chloro-5-cyano-aniline, 2-cyano-5-chloroaniline, 2,4-dicyanoaniline,4-amino The invention is illustrated but not limited by the followingExamples in which all parts and percentages are diphenylamine,4-aminodiphenylmethane, 4- by weight unless otherwise specified.aminodiphenylsulphone, 4-aminobenzene, 4- phenylazo-l-aminoaphthalene,2- 5 EXAMPLE aminobenzenesulphon-N,N-dimethylamide, 2- A mixture of 6.04parts of l-ethyl-4-methyl-5-(2- trifluoromethylaniline, 2- or4-aminobenzonitrile, 2- nitrophenylazo)-6-hydroxypyrid-2-one, 50 partsof diaminophenylmethyl or ethyl sulphone, 4-chloro-2- oxane, 3 parts ofparaformaldehyde and 8.5 parts of pitrifluoromethylaniline, and4-phenylazo-lperidine is heated at the boiling point for 18 hours. Theaminobenzene, y y fl- 10 solution is poured into 400 parts of water andthe preaminobenlene, -p y cipitated Mannich Base having the formulaaminobenzene, 4-4-methylphenylazo-laminobenzene,4-(2',4-dinitrophenylamino)-1- 0 aminobenzene, 4-(2-nitrophenylamino)-l-3 aminobenzene, l-aminonaphthalene, and 6-methyl-2- N a N CH(4-aminophenyl)benzthiazole. x

The azo dyestuff salts of the invention are valuable for obtainingcolorations which are stronger in shade 2 0 OH than those obtained usingknown cationic dyestuffs in C H polymeric materials particularly in theform of textile 2O 5 materials especially those containing polymers andcopolymers f l i il d f di h l d and melting at 158C is collected byfiltration, washed polyester, polyamides and cellulose esters. Thepolywith Water and dfiedmeric materials may be modified, for exampleacid- 1 P of the dyestuff Prepared as described above is modified. Thedyestuff free base, when ground with a dissolve? in mixture of 5 P m fwater and 9- Parts solid water-soluble carboxylic acid, may be pastedwith of acetic and the Solution dilute? 3000 aqueous acetic acid anddissolved water giving an parts of water. 100 parts of polyacrylonitrilefibre as aqueous Solution Suitable for use in dyeing Alterna 1mmersed 1nthe solution and the temperature IS raised tively the dye free base maybe dissolved in a suitable -slowly to 100 and dyemg commued at thlstempera' solvent, preferably an aqueous organic carboxylic acid, turefor 90 p which may optionally contain a further solvent, giving Theresumng f greemsllyenow shade has a Concentrated liquid formulationwhich does not form excellent fastness to light, washing and heattreatment. a sediment or crystallize on low-temperature storage. EXAMPLE2 These d estuff salts of the invention ma be a lied to polyam ide,cellulose ester. or particu larly g lya- In place 9 the parts ofp'perldm? used m Exam crylontrilc or polydicyanoethylene materials fromacid, ple 1 here ls'used parts of morphohne whereby the or neutraldyebaths (i.e. pH from 3 to 7) at tempertures l h. l f lll between 40and 120C and preferably between 80 and l20C or by printing techniquesusing thickened print pastes. 40 N m N Gill n On polyacrylonitriletextile materials, especially when the polyacrylonitrile has beenmodified to con tain acidic groups, bright shades are obtained which are0 m on distinguished by their good wet and light fastness and l build upproperties. 5 2 5 These dyestuffs are particularly valuable forcoloration, preferably from neutral dyebaths, of polyamide and meltingat 196C is obtained. and polyester polymeric materials which aremodified The dyestuff yields greenish-yellow dyeing having exto containacidic groups. cellent fastness to light, washing and heat treatments,The azo dyestuffs of the invention are also valuable when applied topolyacrylonitrile fibres from an aqueas dyestuffs and may be appliedfrom aqueous disperous acetic acid dyebath. sion to polyamide, celluloseacetate and triacetate and The following examples were prepared in asimilar polyester fibres. manner:

EXAMPLE A T v x SHADE 3 Lnitrophenyl (H .H pipuridino greenishyellow 4Lmclhoxy-t-nitrophenyl do. do. do. lllllll 5 4 methoxy-2-nitrophenyl do.do. do. :l't-lloll'ishorange 6 4-methyl-' -nitrophenyl do. do. do. mid

yellow 7 phenyl do. do. do. greenish yellow 8 Z-methylphcnyl do. do. do.mid

\'ello\\- 9 3-methylphenyl do. do. do. do. 10 4-m'ethylphenyl do. do.do. do. I l 2-methoxyphenyl (2H5 pipcridino mid EXAMPLE A T V X SHADE l24-methoxyphenyl do. do do. do l3 4-ueetylaminophenyl do. do do. do l4Z-chlorophenyl do. do do. greemshvellow l5 4-ehlorophcnyl do. do do. dol6 4-nitrophenyl do. do do. do 17 Z-nitro-4-chlorophenyl do. do do. dol8 2-ehloro-4-nitrophenyl do. do do. do I) Z-hromo-4-nitrophenyl do. do.do. do 20 3-chlorophenyl C-,H,-, do. do. do 2l 4-sulphonamidophenyl CH;do. do. do 22 Z-nitrophenyl do. C-H OH do. do 23 do. do. C H OCH do. do24 do. do. 1 do. do 25 do. do. H do. do. 26 do. do. p-tolyl do. do. 27Z-nitrophenyl CH C H; do. do. 28 do. do. o-tolyl do. do. 29 do. do. pdodo.

methoxyphenyl 30 do. do. pdo. do

nilrophenyl 3 l do. do. ldo. do.

naphthyl 32 4-methoxynitrophenyl do. C. ,H,, morpholino reddishyellow 33do. do. do. thiodo.

morpholino 34 4-methoxy-2-nitrophenyl CH C. .H;, -N(CH reddishyellow 35do. do. do. -N(CH )-C- H ,CN do. 36 do. do. do. -N(CH;,)-C H OH do. 37do. do. do. -N(C H OH) do. 3X 'l-nitrophenyl do. do. hexuhydrouzepinogreenishyellow 3) do. do. do. -N(C H OH)- do. -10 do. do. do.-N|CH(CH;,)- do. 4| do. do. do. 2-methyldo.

pyrrolldino 42 do. H CH piperidlno do. 43 do. C H do. do. do.

EXAMPLE 44 are added with stirrmg to a mixture of 5 parts of acetic 2.5Parts of a dyestuff 4O acld and 5 parts of water, and the mrxturestlrred for 20 M mmutes at room temperature. A m0b1le yellow-hquld,

stable on low temperature storage 1s obtamed.

A slmllar procedure usmg the dyestuffs llsted below N a H 2 glvescolored polyacrylontnle fabrlcs of the shade 1nd1- 45 sa ed. m i

c ll

EXAMPLE A 'I Y X SHADE 4S 4-methoxy-2-nitrophenyl CH H Piperidinoreddishyellow 46 phenyl do. do. do. greenishyellow 47 4-methylphenyl do.do. do. mid-yellow 48 Z-methylphcnyl do. do. do. do. 49 4methoxyphenyldo. do. do. do. 50 Z-methoxyphenyl do. do. do. do. 5]4-ucetyluminophenyl do. do. do. do. 52 4-sulphonznnidophenyl do. do. do.greenish yellow 53 4-(phenyluzolphenyl do. do. do. reddish \ellow 544-(2'-methylphenyluzo)- do. do. do. yellow- 2-methylphenyl orange 55l'-n'.lphthyldo. do. do. orange 5 4-(2.4'-dlnitrophenyl) do. do. do.reddishuminophcnyl yellow 57 Z-nilrophenyl do. do. morpholinoGreenishyellow EXAMPLE 58 9.06 parts of adyestuff f formul a: W

are suspended in 25 parts of chlorobenzenc, and 4.5 parts ofparaformaldehyde and 13 parts of piperidine added. The resulting mixtureis heated at 95 100 for 18 hours, and the chlorobenzene removed bysteam- Hyflo Spcrcel at 70, screened hot and the filtrate ba- 20 sifiedwith aqueous ammonia. 9 Parts are obtained of a dycstuff of formula:

EXAMPLE 72 2.5 Parts of the dyestuff described in Example 1 are added toa stirring mixture of 1 part of acetic acid, 1 part of methanol and 8parts of water, and the solution stirred for 20 minutes at roomtemperature. A mobile yellow liquid, stable on low temperature storage,is obtained.

EXAMPLE 73 By replacing the methanol in Example 72 by l part of ethanol,a similar mobile concentrated liquid formulation is obtained.

EXAMPLE 74 By replacing the methanol in Example 72 by l part ofisopropanol, a similar concentrated liquid composition is obtained.

We claim:

1. A water soluble salt of an azo dyestuff free from sulphonic orcarboxylic acid group of the formula:

2.5 Parts of the dyestuff described in Example 1 are added to a stirringmixture of 1 part of acetic acid and 65 A-N= N H 2x wherein A is2-nitrophenyl, 3-nitrophenyl, 4-nitrophenyl, 2- of l i g i lg i g gmethoxy-4-nitrophenyl, 4-methoxy-2-nitrophenyl, 0 Su p amlc. an pas e o0 4-methyl-2-nitrophenyl, phenyl, 2-methylphenyl, aqueous acetic acid,and the resulting fluid mixture dish 1 h l 4 [h l h 1 2 35 met yp eny-met yp eny, solved in 200 parts of water giving a 0.5% aqueoussomethoxyphenyl, Lmethoxwhewl, lution which can be used to dyepolyacrylontrile by the acetylaminophenyl LehlomPhew], applicationmethod described 1n Example 1. chlorophenyl, 4-chlorophenyl, 2- i -4Tl'llS dye produces similar shades on polyacrylontrile chlorophenyl, gchloro 4 nitrophenyl, g -4 to the dyestuff Of Example 40 nitrophenyl,4-sulphonamidophenyl, 4' Other dyestuffs of the invention, prepared bythe (phenylazo)phenyl, 4-(2'-methylphenylazo)-2- method used in Example58 are listed as follows: methylphenyl, l'-naphthyl-., 4-(2,4'-dinitro-Ex. A r Y x SHADE 5) 4-methoxy-Z-nitrophenyl CH;I (2H3 piperidinoreddish yellow ((1 Z-nitrophenyl do. phenyl do. greenish yellow 61 do.do. p-chlorophenyl do. do. 62 4-(phenylazo)phenyl do. C H do.reddishyellow 63 4 (2'methylphenylazo)- do. do. do. do.

2 methylphenyl 64 4-(phenylazoLZ-chlorodo. do. do. do.

phenyl 65 4-(4'methylphenylazo) do. do. do. do.

phcnyl m1 4-( 2'.4'-dinitrophenyldo. do. do. do.

amino)phenyl o7 4-(2'-nilrophenylamin0)- do. do. d d

phcnyl (t8 l'maphthyl do. do. do. do. 9 6-mcthyI-2-(4' amlno do. do. do.yellow phenyllhenzthiazole 7U Z-nitrophenyl phenyl do. do. do.

7 EXAMPLE 71 phenyl)aminophenyl, 4-(phenylazo)-2- chlorophenyl,4-(4-methylphenylazo)-phenyl, 4- (2-nitrophenylamino) phenyl,. or6-methyl-2-(4'- aminophenyl) benzthiazole;

T is methyl, ethyl, propyl or phenyl;

Y is hydrogen. methyl. ethyl. propyl. hydroxycthyl. methoxypropyl.l-naphthyl. phenyl. p-tolyl. o-tolyl.

selected from the group consisting of hydrochloric, sulphuric,phosphoric, sulphamic, boric, formic, acetic, propionic, citric, oxalic,and mono-, diand trichloroacetic acids.

2. The dyestuff of claim 1 wherein A is orthonitrophenyl.

3. The dyestuff of claim I wherein X is piperidino.

1. A WATER SOLUBLE SALT OF AN AZO DYESTUFF FREE FROM SULPHONIC ORCARBOXYLIC ACID GROUP OF THE FORMULA:
 2. The dyestuff of claim 1 whereinA is ortho-nitrophenyl.
 3. The dyestuff of claim 1 wherein X ispiperidino.